Sewing machine



Feb. 4 1936. RAPAPORT ET AL 2,029,942

SEWING MACHINE Filed Nov. 18, 1932 4 Sheets-Sheet 1 F ig. Ia.

v nna/J15) Feb. 4, 1936. N RA APORT Er AL 2,029,942

SEWING MACHINE Filed Nov. 18, 1932 4 Sheets-Sheet 3 (WQM . ATTORNE BYgar/92:4 am

Feb. 4, 1936. RAPAPORT ET AL 2,029,942

SEWING MACHINE Filed Nov. 18, 1932 Sheets-Sheet 4 Y/ A l// A PatentedFeb. 4, 1936 UNITED STATES PATENT OFFlQE SEWING MACHINE ApplicationNovember 18, 1932, Serial No. 643,276

In Great Britain 33 Claims.

This invention relates to sewing machines, for embroidery or otherdecorative sewing, of the kind having at least one needle, means forreciprocating the needle axially, means for shifting or throwing theneedle to and fro laterally to a controllable or variable extent, aneedle thread supply, an under thread supply, and a rotary hook whichenters loops formed in the needle thread below the fabric and serves. tointerengage said loops with the under thread, the needle reciprocatingand throwing means and the hook being actuable in timed relationship.

Known machines of this kind have been capable of satisfactory workwithin a limited needle 5 throw, which has usually been achieved bymounting the needle-bar for reciprocation in a pivotally suspendedcarrier and vibrating the carrier through a so-called cross-over crankwhich is reciprocable in a substantially horizontal direction withvariable stroke under the machine operato-rs control exercised through aknee-lift lever. The factor that has hitherto limited the extent ofthrow is the necessity for the rotary hook, which turns in a path ofsmall radius about a fixed centre, to engage the loop formed by theneedle below the base fabric in the needle thread, notwithstanding thatthe successive reciprocations of the needle form loops at differentpoints in the path of the hook. Satisfactory operation has only beenachieved over the small upper are of the hook path where the said pathand the line drawn through the lower limits of the needle strokes indifferent lateral positions have been substantially parallel, and evenso, to maintain the time period of the coincidence of the hook and theneedle in the sequence of operations substantially unaffected, it hasbeen necessary to employ special mechanism imparting an irregular speedof rotation to the hook despite the limitation of the needle throw.Withal, the known machines are liable to execute faulty work by reasonof the hook failing to engage the needle thread loops in the extremelateral positions of 45 the needle throw.

Now th present invention makes it possible to attain not only certaintyof engagement of the needle thread loops by the hook at the heretoforeknown limits of throw, but optionally a much 50 greater throw, up toabout the diameter of the hook path, with the same certainty ofoperation.

The invention provides means for varying the height at which the needlereciprocates, in dependence on the lateral throw imparted to the 55needle, in such manner as to ensure proper November 30, 1931 (Cl.112i58) presentation of the needle thread loop to the hook in alllateral positions of the needle.

The means for raising and lowering the height of the needle as it isthrown laterally is or may be such that the time taken for the needle in5 any line of reciprocation to pass and repass the eifective arc of thehook path is equal to the time taken by the hook to reach the said line.

The invention also provides means for effecting a lateral throw of theneedle up to an 10 extent substantially equal to the diameter of thehook, and means for ensuring proper presentation of the needle threadloop to the hook in all lateral positions of the needle.

Any of the means as aforesaid may be incor- 15 porated in a machinedesigned to comprise them, or any of the said means may constitute anattachment for the existing machines of the. kind set forth.

Another disadvantage to which the known ma- 20 chines have been subjectheretofore is that the tension on the needle thread has been controlledby a take-up lever and an adjacent friction device from which the threadpasses to the lever, so that the tension of the thread has been the 25same irrespective of the varying throw of the needle. This, even withthe limited maximum throw hitherto obtainable, has been objectionable,and in some cases has resulted in shirring of the base fabric. 0

To overcome this defect the invention provides means whereby the tensionexerted by the said friction device on the needle thread isautomatically decreased or increased inversely with increase or decreasein. the lateral shift or throw 35 of the needle, so that the saiddisadvantage arising from constant thread tension is avoided, and alsoincreased throw of the needle may be employed without the quality of thework being im- 40 paired by excessive thread tension.

By way of example the invention will now be described as applied to anexisting machine similar to the commercial Singer Sewing Machine107w100.

In the accompanying drawings:-

Fig. 1 is a fragmentary elevation of the machine;

Fig. la. is a fragmentary elevation of certain of the existing detailsof the machine;

Fig. 1b is a plan view of the said details;

Fig. 2 is an end view of the novel means shown in Fig. 1;

Fig. 3 is a diagram illustrating a feature of the said means;

Figs. 4 and 5 are diagrams illustrating the operation of the said means;

Fig. 6 is an elevation of a constructional form of the hereinbeforementioned means for automatically varying the thread tension;

Fig. 7 is a sectional elevation on the line VIIVII of Fig. 6;

Fig. 8 is a perspective view of the whole machine head showing thecorrelation of various known parts thereof with the means according tothe invention; and

Fig. 9 is an elevation showing a modification or development of theinvention for employing two needles simultaneously.

From the drawings it will be evident to those skilled in the art thatmany parts of the machine are retained unchanged. However, reference tosome of these parts and their function or operation is first necessaryin order that the present invention may be clearly understood. Themachine head I is mounted over the work table 2, and encloses mechanismfor operating from the shaft of the flywheel pulley 6 (Fig. 8) theneedlebar 3, the cross-over crank 4 and the rotary hook 5. The head alsosupports the double presser foot assembly I, the thread spool mounting8, the means 9 serving for the initial lateral positioning of theneedle, and the linkage system III, II,

, |2, |3 (Fig. 6) serving to transmit the movements of the knee-liftlever (not shown) for controlling the throw of the needle duringoperation of the machine. The cross-over crank 4 is actuated by the cam|4 (Figs. 1a, and 11)) secured to the cross shaft I5 and engaging thefork l6 formed at the end of the crank 4, which end is supported by thelink I! pivoted to the crank at l9. The link I! is in turn pivoted onthe pin 20 carried by the crank 2|, which is fast on the shaft 22. Thesaid shaft 22 is turnably mounted in and bodily movable by the link 23,which is itself turnable by the lever 9 (Fig. 6). With this lever in theposition shown the: stitches are formed to the right of a datum line;when the lever 9 is moved so that the pin 9a thereon engages theaperture 91), the consequent displacement of the link 23 and shaft 22causes the stitches to be eifected equally on both sides of the datumline; and when the lever 9 is moved so that the pin 9a engages theaperture 90, the displacement of the link 23 and shaft 22 causes thestitches to be formed to the left of the datum line. The shaft 22 alsohas secured to it the crank-lever 3 (Fig. 6) movement of which, by theknee-lift lever, through the linkage H], II, l2, turns the shaft 22.Thus the crank 2| can be turned to a controllable ex tent to change theposition of the pin 20. When the crank 2| is turned to a positionapproaching the horizontal, the forked end l6 of the cross-over crank 4is merely raised and lowered by rotation of the cam l4, the pivot l9describing a vertical are about the pin 26, and the horizontal movementimparted to the cross-over crank being very small; but when the crank 2|is turned towards the vertical (as shown in Fig. 1a) the are describedby the pivot 59 acquires a greater horizontal component, the horizontalmovement imparted to the cross-over crank 4, and consequently the throwof the needle, being correspondingly increased. The needle is mountedfor reciprocation in a swing carrier (not shown.) and normally the crank4 is connected to and so oscillates the said swing carrier.

All the foregoing features are known.

For the purpose of the invention the swing carrier is locked againstswinging movement, for

example by a set screw, and, as shown in Figs. 1 to 5, an attachment isprovided comprising a plate 24 secured to the needle-bar 3 and havinghorizontal guides 25 serving to guide a second plate 26. This secondplate 26 has vertical guides 2! in which a block 28 constituting aholder for the needle 29 is movable. This block or needle holder 28 hasa pin 36 projecting from its back and passing through an aperture 3| inthe second plate 26 to enter a cam slot 32 in the plate 24. Ananti-friction roller may be provided on the pin to engage the walls ofthe cam slot. The lateral movement of the needle is now achieved bymoving the second plate 26 along the slides 25. The movements of theplate 26 are received, directly or indirectly, from the cross-overcrank, the end of which is constrained to reciprocate in a horizontal,lateral line by guides 35, 36, 31 on the body of the machine, and a pin38 mounted in: a lug on the said body.

To the attainment of the possibility afiorded, by the means justdescribed, of increasing the lateral throw of the needle substantiallyup to the diameter of the path of the hook 5, a short connecting link 33is pivoted to the cross-over crank at 34, and transmits the horizontalmovement thereof, through a pivotal connection 39, to a multiplyinglever 46. This lever 46 is pivoted at 4| to the body of the machine andat 42 to a block 43 through which extends, with a sliding fit, avertical rod 44 projecting upwardly from 9. lug. 45 forming part of thesecond plate 26. The sliding engagement of the block 43 and the rod 44enables the plate 26 to be moved laterally through the link 33 and thelever 40 notwithstanding that the plate 26, and the rod 44 secured toit, reciprocate vertically with the needle-bar 3.

In order to provide for an initial adjustment of the needle in its pathof lateral shift, the short link 33 may be adjustable as to length.Further, to enable the length of throw of the needle to be initiallyadjusted, the point of connection of the link 33 and lever 40 mayobviously be made adjustable along the length of the lever.

The function of the attachment may be understood by consideration ofFig. 3. The hook 5 moves in a circular path (of which the effective areis that above the diameter XOX) below a slot in the work table 2,through which the needle passes at each stroke. Irrespective of thelateral position of the needle, the stroke is of a constant length a,being determined by the stroke of the needle-bar 3; however, as may beseen from Fig. 3, the upper and lower limits of the stroke a are changedin accordance with every change of position of the pin 30 (which issecured to the needle block 28) in the cam slot 32. In the developmentof the invention, consideration has shown that the primary function isto bring the needle to such a position at every reciprocation that theloop formed in the upper thread below the base fabric extends across thepath of the hook at the time when the hook passes the needle.Preferably, also, the common practice of having the needle past itsbottom dead-centre and commencing to rise at the time of engagement ofthe loop by the hook is to be retained. As a basis for the derivation ofthe true shape of the cam slot 32, the locus of the lower dead-centresof the needle strokes with various throws might be considered as an arcof radius equal to that of the path of the hook, and vertically belowthe said path. This, however, neglects the time taken for the rotationof the hook from a datum line OX into the line of reciprocation of theneedle during a particular stroke. For example, when the pin 30 is atthe extreme left of the slot 32, the hook has to rotate from the line OXthrough the angle 0, while for every successive position of the pin 30towards the right of the slot 32 the angle through which the hookrotates is progressively smaller than the angle 0. It has therefore beenfound desirable to lower the bottom dead-centre of the needle stroke ato a maximum extent b below the path of the hook for the extreme leftposition of the needle, and to a progressively smaller extent to theextreme right position. Thus, in the extreme left position the timetaken for the hook 5 to rotate through the angle corresponds to the timetaken by the needle to rise from its lower dead-centre through thedistance I), and the loop in the needle. thread is correctly positionedfor engagement by the hook; similarly, the times occupied by therotation of the hook and the rise of the needle are correlated for everyposition, and perfect engagement of the thread loops by the hook isattained up to the limits of the needle throw, notwithstanding that thelength of the said throw may approximate to the diameter of the path ofthe hook and that at the one extreme the hook is rising practicallyvertically while at the other extreme the hook is descending practicallyvertically. For effecting the said lowering of the lower dead-centre ofthe needle strokes in the positions towards the left, the cam slot 32 isshaped substantially as shown in Fig. 3 of the drawings, being not quitesymmetrical about a vertical line, but having its left end lower thanits right end. On account of the irregularity caused in the speed of thehook in accordance with the throw of the needle by the mechanism ofcertain known machines, the decrease in the lowering of the needle maynot be exactly uniform from left to right when the invention is appliedto such machines. Nevertheless, the shape of the slot 32 is but a slightmodification of that shown in Fig. 3. With a cam slot exactly as shown,it is obviously possible to eliminate if desired the mechanism hithertospecially provided for imparting irregularity of speed to the hook, andthus to employ a hook having a uniform speed.

When, according to the invention, the throw of the needle is increased,it is desirable, and may be necessary, to set back, as by grinding orotherwise, the nose of the usual base member (not shown) about which thehook rotates, so that thread loops taken up by the hook, even at theextreme left-hand needle position, may subsequently be transferred tothe said nose in the ordinary manner of sewing.

Figs. 4 and 5 show the attachment with the needle at lower dead-centrein its extreme right and left positions respectively. In each case thehook 5 is in its datum position as described with reference to Fig. 3,but it will be observed that 'in Fig. 4 by virtue of the dropping of theleft end oi the cam slot 32 the needle block 28 and the needle 29 arelower than in Fig. 5, where the pin 36 is in the higher right end of thecam slot.

As has been mentioned hereinbeio-re, the known machines of the kind withwhich the invention is concerned sulfer a disadvantage arising from thefact that the thread tension remains unchanged despite variations in thethrow of the needle. With the means as hereinbefore describedpermitting, if desired, an increase in the needle throw, it. is evenmore desirable to avoid any possibility, of the tension of the needlethread spoiling the effectiveness of the work of the machine.

possible by forming the rod 41 in two parts slotted at 48 toreceivebolts 49. Also, the relative amounts of turning of the arm I la and thelever 46 are made adjustable by attaching the rod 41 to the arm Ila bymeans of a pivot 50 engaging a slot 5| in the said arm. The lever 46 ismounted on a pin 52 supported in the body I of the machine, and atoothed quadrant 53 is also mounted on the pin so as to be turnable withthe lever 46. The quadrant meshes with a toothed pinion 54, the hub ofwhich is screw-threaded internally and engages a screw-thread formed ona pin 55 carrying a pair of conical thread-tension plates or washers 56and compression control spring 5?. In the operation of sewing, a thread58 passes from a spool or bobbin 59 on the mounting 8 through eyes 60and 6| in the upper and lateral parts respectively of a wing '62 on themachine head, and thence between the plates '56 of the friction device.Thereafter the thread passes to the usual take-up lever 63 and theneedle. It will be evident that, in the controlling of the throw of theneedle, as the bell crank I l is from time to time turned on its pivot,the arm Ha through the linkage 46, 41 and the toothed quadrant 53 willturn the pinion 54, causing it, by reason of its screw-threaded mountingon the pin 55, to move axially on the said pin, thereby decreasing orincreasing the pressure of the spring 57 upon the plates 56 andcorrespondingly changing the tension of the needle thread. The nature ofthe screw-thread connection should evidently be such that as the needlethrow is increased the pinion 54 is moved outwards on the pin 55 toslacken the thread tension, and as the needle throw is decreased thepinion 54 is moved inwards to increase the thread tension.

Fig. 8 shows the complete assembly of a machine, with. an attachment forraising and lowering the limits of the needle stroke in accordance withthe lateral throwing of the needle block 28 on the plate 24; linkage 33,40 for obtaining an increased throw of the needle block from thecross-over crank 4 without modifying the mechanism provided in themachine for reciprocating the said crank; and auxiliary arm I laactuating, through the linkage 46, 4'! and the quadrant 53, the pinion54 which controls the tension of the needle thread.

A modification of the attachment as above de scribed, illustrated inFig. 9 of the drawings, is fitted with two needles, for sewing patternsin two colours simultaneously or for sewing divided patterns, such assplit leaves, in one colour or two colours. The attachment comprises theplate 24 attached to the needle-bar 3, and carrying a second platehaving a slide 21 upon which the needle block 28 is vertically movable,the only 'diiierence being that the slide 2'! is constituted by acentral under-cut rib which the block 28 is adapted slidably to embrace.The plate 26 is movable horizontally in the slides 25 by the crossovercrank 4, an extension 4b of which engages the vertical rod 44 by meansof a block 43 slidable on the rod. The needle block 28 carries above theneedle 29, a pin 30 engaging the cam slot 32 in the plate 24. Inaddition, the modified attachment carries a second needle block 28a,mounting a needle 29a and slidably supported on the guide 21a of a plate25a horizontally movable in the slides 25. The plate 26a has a lug 45asupporting a vertical rod 44a, which is slidably embraced by a block 43apivoted to an additional cross-over crank 4a, whereby the plate 26a ismoved in the slides 25. Above the needle 29a, the block 2801. alsocarries a pin 35a engaging the slot 32. The blocks 28 and 2811 areadapted for the pins 39, 30a to be brought close together in the slot 32when necessary, the needles 29, 29a also being then close together.

In the machines to which the aforesaid attachments are applicable, forthe assistance of the operator in controlling the work and with themeans 9 in the position shown in Fig. 6, all the stitches commence fromthe left-hand edge of the pattern, so that it is only necessary for thebase fabric to be moved with the said edge of the pattern under theextreme left position of the needle, the knee-lift lever being operatedto control the length of the lateral throw, so that thread is carried onalternate throws to the right-hand edge of the pattern. With themodification having two needles, the operator moves the base fabric topass the left-hand edge of the pattern under the extreme left positionof the left-hand needle, and operates the knee-lift lever to control thelength of the joint throw of the needles so that the throw brings theright-hand needle to the right-hand edge of the pattern. Sewing in thismanner presents no difficulty, as the operator Watches only the totalwidth sewn, the proportions of the respective widths sewn by the twoneedles being determined by means of suitable linkages of the natureshown in Figs. 1a and 1b, modified as may be required (which form nopart of this invention) The respective strokes of the two needles shownin Fig. 9 may be such as toproduce a variety of designs. For instance,in the sewing of a split leaf pattern, whether symmetrical or not, theleft-hand needle may work that side of the leaf to the left of the veinin one colour, while the right-hand needle works that side of the leafto the right of the vein in the same or another colour, the movementsbeing so arranged and controlled that, despite such changes of therespective throws as may be necessary to work the broader and narrowerparts of the leaf, the central vein is not sewn over. As anotherexample, in the sewing of flower petal patterns, where one colour mergesinto another, the strokes of the two needles may be made to overlap,since the controlling linkages may be such as to cause the needles tomove to the left and to the right simultaneously. In this case, at thejuncture of the parts sewn in the two colours there will be a minglingof the threads so that the colours will have an appearance of shadinginto one another. 7

From the foregoing it becomes apparent that the invention affordsseveral possibilities of improvement in the art of embroidery or likesewing, by modification of the known machines, namely:

((1) Increase of needle throw and accuracy throughout the increasedrange with the hook rotating at the customary irregular speed andtherefore without requiring modification of the special mechanism orgearing which rotates the hook;

(b) Increased accuracy over the existing range of needle throw withelimination of the present special mechanism for rotating the hook atan. irregular speed;

(0) Increase of throw, and accuracy throughout the increased range, withelimination of the said mechanism for rotating the hook at an irregularspeed.

A new machine incorporating means according to the invention may, ofcourse, be constructed to realize any of the possibilities (a) (b) or(c) and in a new machine fixed bearings (not a swing carrier) may beprovided for the needle-bar.

In the constructions hereinbefore mentioned the needle moves vertically,i. e. in its own axis perpendicularly to the plane of the work,regardless of the position it occupies along its path of lateral throw.Such a movement is to be preferred for various reasons, and thepossibility of obtaining it by means of the said constructions is anadvantage not present in existing machines with swing frame needle-barcarriers, in which the needle has a movement'perpendicular to the planeof the work only when it happens to be located at one particular point,such as the midpoint of its lateral throw. At all the other points ofthe said throw the needle is inclined, more or less, to the plane of thework.

The invention also confers several further advantages. The obviousadvantage of being able to execute large patterns (without the necessityfor going over the work in a number of strips, or first executing amarginal strip and then seeding in the middle portion) itself results ina remarkable increase in the speed at which work may be executed. Apartfrom this, the absolute certainty with which the hook takes up theneedle thread loops, even at the extremes of the lateral throw, preventsWaste of time in unpicking and repeating work on account of droppedstitches, and also waste of thread. In the case where advantage is takento use a hook rotating at uniform speed, the consequent better balanceand reduced friction of the moving parts further enables the machine tobe operated at an absolute speed much greater than has hitherto beenpracticable, this speed being limited only by the skill of the operator.

The embroidery machines have been hereinbefore described as having onlyone hook co -operating with a single needle or a single group ofneedles. It will, however, be understood that the invention may beapplied to machines for special purposes having a plurality of hooksco-operating with a like plurality of needles or groups of needles.

We claim:

1. In a sewing machine, the combination of means for reciprocating theneedle axially, means for throwing the needle to and fro laterally to avariable extent in a plane transverse to the line of sewing, arotaryhook actuable in timed relationship with the needle reciprocatingand throwing means, manually-controlled means for varying the extent ofthe needle throwing at the will of the operator, and means varying theheight at which the needle reciprocates in dependence on the variablelateral throw imparted to the needle and thereby ensuring properpresentation of the needle thread loops to the hook in all of thevariable lateral positions of the needle.

2. In a sewing machine, the combination of means for reciprocating theneedle axially, means for throwing the needle to and fro laterally to avariable extent in a plane transverse to the line of sewing, a rotaryhook actuable in timed relationship with the needle reciprocating andthrowing-means, manually-controlled means for varying the extent of theneedle throwing at the will of the operator, and means raising andlowering the height of reciprocation of the needle as it is variablythrown laterally, said means causing such change of the height ofreciprocation that the time taken for the needle in any line ofreciprocation between the limits of variable lateral throw to rise fromits lower dead centre to the effective are of the hook path is equal tothe time taken by the hook to reach the line of reciprocation.

3. In a sewing machine, the combination of means for reciprocating theneedle axially, means for throwing the needle to and fro laterally to avariable extent in a plane transverse to the line of sewing, a rotaryhook actuable in timed relationship with the needle reciprocating andthrowing means, and means raising and lowering the height ofreciprocation of the needle as it is variably thrown laterally, saidlast mentioned means maintaining the needle vertical and causing. suchchange of the height of reciprocation that the time taken for the needlein any line of reciprocation between the limits of variable lateralthrow to rise from its lower dead centre to the effective are of thehook path is equal to the time taken by the hook to reach the line ofreciprocation.

4. In a sewing machine, the combination of means for reciprocating theneedle axially, a rotary hook actuable in timed relationship with theneedle reciprocating means, means effecting variable lateral throwing ofthe needle up to an ex,- tent substantially equal to the diameter of thehook, means maintaining the needle vertical in all lateral positions,and means ensuring proper presentation of the needle thread loops to thehook in all lateral positions of the needle.

5. In a sewing machine, the combination of means for reciprocating theneedle'axially, means for throwing the needle to and fro laterally to avariable extent in a plane transverse to the, line of sewing, a rotaryhook actuable in timed relationship with the needle reciprocating andthrowing means, and cam means connecting the needle-reciprocating meanswith the needle and serving to vary the height at which the needlereciprocates in dependence on the variable lateral throw imparted to theneedle, the cam means ensuring proper presentation of the needle threadloops to the hook in all lateral positions of the needle.

6. In a sewing machine, the combination of means for reciprocating theneedle axially, means for throwing the needle to and fro laterally to avariable extent in a plane transverse to the line of sewing, a rotaryhook actuable in timed relationship with the needle reciprocating andthrowing means, and pin-and-slot means connecting theneedle-reciprocating means with the needle and serving to raise andlower the height of reciprocation of the needle as it is variably thrownlaterally, the pin-and-slot means causing such change of the height ofreciprocation that the time taken for the needle in any line ofreciprocation to rise from its lower dead centre to the efiective arc ofthe hook path is equal to the time taken by the hook to reach the lineof reciprocation.

7. In a sewing machine, the combination of means for reciprocating theneedle axially, a rotary hook actuable in timed relationship withthe'needlereciprocating means, means effecting variable lateral throwing ofthe needle in a plane transverse to the line of sewing up to an extentsubstantially equal to the diameter of the hook and cam means connectingthe needle-reciprocating means with the needle and serving to ensureproper presentation of the needle thread loops to the hook in alllateral positions of the needle. 8. In a sewing machine, the combinationof means for reciprocating the needle axially, means for throwing theneedle to and fro laterally to a variable extent in a plane transverseto the line of sewing, a rotary hook actuable in timed relationship withthe needle reciprocating and throwing means, a lever included in theneedle-throwing means imparting a multiplied variable throw to theneedle, and pin-and-slot means connecting the needle-reciprocating meanswith the needle and serving to ensure proper presentation of the needlethread loops to the hook in all lateral positions of the needle. I

9. In a sewing machine, the combination of means for reciprocating theneedle axially, means for throwing the needle to and fro laterally to avariable extent, a rotary hook actuable in timed relationship with theneedle reciprocating and throwing means, manually-controlled means forvarying the extent of said needle throwing at the will of the operator,and cam means connecting the needle-reciprocating means with the needleand serving to raise and lower the height of reciprocation of the needleas it is variably thrown laterally, the cam means maintaining the needlevertical and causing such change of the height of reciprocation that theneedle reciprocates to lower dead centres which are progressively at aless distance below the effective are of the hook path as the needle isthrown to successive lines of reciprocation from the end to thebeginning of said are.

10. In a sewing machine, the combination of means for reciprocating theneedle axially, a rotary hook actuable in timed relationship with theneedle reciprocating means, means effecting variable lateral throwing ofthe needle in a plane transverse to the line of sewing up to an extentsubstantially equal to the diameter of the hook, means maintaining theneedle vertical in all lateral positions, and pin-and-slot meansconnecting the needle-reciprocating means with the needle and serving toimpart to the needle as it is moved to successive lines of reciprocationfrom the beginning to the end of the effective arc of the hook path suchchanges of height that the needle reciprocates to lower dead centreswhich are progressively at a greater distance below said arc.

11. In a sewing machine, means comprising in combination a membervertically reciprocable between fixed limits, a rotary hook, a membersupported by the said member and laterally movable parallel to the planeof the hook, a needle-holding member vertically movable on the laterallymovable member, means imparting variable lateral movements to thelaterally movable member, and a pin on the needle-holding memberengaging a cam slot associated with the vertically reciprocable member,said pin and slot varying the height at which the needle reciprocates independence on the variable lateral movements imparted to the needle, andensuring proper presentation of the needle thread loops to the hook inall lateral positions of the needle.

12. Ina sewing machine, the combination of a rotary hook, a membervertically reciprocable between fixed limits, a member supported by thesaidmember and laterally movable parallel to the needle as it is movedto successive lines of reciprocation from the beginning to the end ofthe effective arc of the hook path such changes of height that theneedle reciprocates to lower dead centres which are progressively at agreater distance below said arc.

13. In a sewing machine, means comprising in combination a rotary hook,a needle bar vertically the height of reciprocation of the needle thatthe time taken for the needle in any line of reciprocation to rise fromits lower dead centre to the effective arc of the hook path is equal tothe time taken by the hook to reach the line of reciproca- -tion.

14. In a sewing machine, the combination of a rotary hook, of a needlebar vertically reciprocable between fixed limits, lateral guide meanssupported by the needle bar, a member variably laterally slidableparallel to the plane of the hook on the said guide means, verticalguide means on the said member, a needle block slidable on the verticalguide means, a cam slotted member supported by the needle bar, a pin onthe needle block engaging the cam slot, and means for effect- -inglateral throwing of the needle up to an extent substantially equal tothe diameter of the hook, said slot being shaped to ensure properpresentation of the needle thread loops to the hook in all lateralpositions of the needle.

15. In a sewing machine, the combination of 'a needle bar verticallyreciprocable between fixed limits, lateral guide means supported by theneedle bar, a member laterally slidable on the said guide means, meansfor throwing said laterally slidable member to and fro, a rotary hookactuable in timed relationship with said needle bar and said throwingmeans, a multiplying lever included in said throwing means, verticalguide means on the said member, a needle block slidable on the verticalguide means, the lateral 'guide means having a cam slot, and a pin onthe needle block engaging the cam slot, said slot being shaped to ensureproper presentation of :the needle thread loops to the hook in alllateral positions of the needle, a vertical extension on the laterallyslidable member, and a block member slidable in the extension andpivoted to the lever, throwing movements multiplied by the lever beingtransmitted through the block member and the extension to the laterallyslidable member without hindering the vertical reciprocations of thelaterally slidable member.

16. In a sewing machine, means comprising in combination a membervertically reciprocable between fixed limits, needle throwing means, arotary hook aotuable in timed relationship with said member and saidmeans, a laterally movable -member supported by the said member, aneedleholding member vertically movable on the laterally movable memberand a pin on the needleholding member engaging a cam slot associatedwith the vertically reciprocable member, a vertical extension on thelaterally movable member,

a yoke member slidably embracing the extension, the said yoke memberbeing operatively connected to the needle-throwing means andtransmitting needle-throwing movements through the extension to thelaterally movable member without hindering its vertical reciprocations,and the said cam slot being shaped to cause such change of the height ofreciprocation of the needle as it is thrown laterally that the timetaken for the needle in any line of reciprocation to rise from its lowerdead centre to the effective are of the hook path is equal to the timetaken by the hook to reach the line of reciprocation.

1'7. In a sewing machine of the kind set forth and having a take-uplever and an adjacent friction device from which the needle threadpasses to said lever, said device controlling the tension of the needlethread, the combination of a knee-lift lever aotuable by the operator tocontrol the extent of the needle throw, spring loading means in saidfriction device, and means aotuable by the knee-lift lever to relievesaid spring loading progressively as the needle throw is increased, andvice versa.

18. In a sewing machine of the kind set forth, the combination of aknee-lift lever aotuable by the operator to control the extent of theneedle throw, a take-up lever, a needle thread tensioning deviceadjacent said take-up lever, from which said thread passes to saidlever, comprising a pair of friction members and spring means pressingsaid members together, an externally screw-threaded member supporting aninternally screw-threaded member which abuts said spring means, andlever means operatively connected with said knee-lift lever for turningsaid internally threaded member and thereby moving it axially to varythe stress in said spring 19. In a sewing machine of the kind set forth,

the combination of a knee-lift lever actuable by the operator to controlthe extent of the needle throw, a thread tensioning device comprising astud, a pair of conoidal washers supported on the stud, an externallyscrew-threaded portion on the stud, an internally screw-threaded pinionseated on said portion, a coil spring surrounding the stud and abuttingthe pinion and one of the washers, a fixed stop abutting the other ofthe washers, a toothed quadrant meshing with the,

pinion, and lever means operatively connected with the knee-lift leverfor turning the quadrant. 20. In a sewing machine having a plurality ofneedles, means for reciprocating the needles axially, means for throwingthe needles to and fro laterally to a variable extent and a coactingrotary hook, means varying the height at which each needle reciprocatesin dependence on the variable lateral throw imparted to it, said meansensuring proper presentation of the needle thread loops to the hook inall lateral positions of th needles.

21. In a sewing machine having a plurality of needles, common means forreciprocating the needles axially, means for throwing the needles to andfro laterally to a variable extent and a co-operating rotary hook, cammeans connecting the needles with the common needle-reciprocating meansand serving to vary the height at which. eachneedle reciprocatesindependence on the Variable lateral throw imparted to it,

said cam means ensuring proper presentation of the needle thread loopsto the hook in all lateral positions of the needles. 1

22. In a sewing machine having a plurality of needles, means forreciprocating the needles axially, means for throwing the needles to andfro laterally to a variable extent, and a co-operating rotary hook,pin-and-slot means connecting the needle-reciprocating means with theneedles and serving to raise and lower the heights of reciprocation ofthe needles as they are variably thrown laterally, said pin-and-slotmeans causing such change of the heights of reciprocation that the timetaken for each needle in any line of reciprocation to rise from itslower dead centre to the effective arc of the hook path is equal to thetime taken by the hook to reach the line of reciprocation.

23. In a sewing machine having a plurality of needles, means forreciprocating the needles axially, and a co-operating rotary hook, thecombination of means effecting variable lateral throwing of the needlesparallel to the plane of the hook up to a total extent substantiallyequal to the diameter of the hook, means maintaining the needlesvertical in all lateral positions, and pinand-slot means connecting theneedle-reciprocating means with the needles and serving to impart to theneedle-s as they are moved to successive lines of reciprocation from thebeginning to the end of the effective are of the hook path suchindependent changes of height that the needles reciprocate to lower deadcentres which are progressively at a greater distance below said arc.

24. In a. sewing machine having a plurality of needles and a co-operating rotary hook, the combination of a needle bar verticallyreciprocable between fixed limits, lateral guide means supported by theneedle bar, a plurality of members laterally slidable on the said guidemeans, vertical guide means on each of said members, a needle blockindependently slidable on the vertical guide means on each of saidmembers, a cam slotted member supported by the needle bar, a pin on eachof the needle blocks engaging the cam slot, and means for effectinglateral throwing of the needles up to a total extent substantially equalto the diameter of the hook, said cam slot being shaped to ensure properpresentation of the needle thread loops to the hook in all lateralpositions of the needles.

25. An attachment for a sewing machine having means for reciprocatingthe needle axially, means for throwing the needle to and fro laterallyto a variable extent, and a rotary hook actuable in timed relationshipwith the needle reciprocating and throwing means, comprising meansraising and lowering the height of reciprocation of the needle as it isvariably thrown laterally in a plane transverse to the line of sewing,said means causing such change of the height of reciprocation that thetime taken for the needle in any line of reciprocation to rise from itslower dead centre to the efiective arc of the hook path is equal to thetime taken by the hook to reach the line of reciprocation.

26. An attachment for a sewing machine having means for reciprocatingthe needle axially, means for throwing the needle to and fro laterallyto a variable extent, and a rotary hook actuable in timed relationshipwith the needle reciprocating and throwing means, comprising incombination a needle-holding member, a lever attachable by pivot meansat its upper end to the mathrowing means imp-art through the lever amultiplied variable throw to the needle-holding member in a planetransverse to the line of sewing, and pin-and-slot means serving toconnect the needle-reciprocating means with the needleholding member andto ensure proper presentation of the needle thread loop-s to the hook inall lateral positions of the needle.

27. An attachment for a sewing machine having needle-reciprocating meansincluding a needle-bar movable vertically in fixed guides between fixedlimits, means for throwing the needle to and fro laterally to a variableextent and a rotary hook actuable in timed relationship with the needlebar and the needle throwing means,

comprising in combination a laterally movable,;g

member attachable to the needle-bar, a needleholding member verticallymovable on said laterally movable member and a pin on saidneedleholcling member engaging a cam slot associated with saidattachable member, said cam slot being :2

shaped to vary the height at which the needle reciprocates in.dependence on the variable lateral throw imparted to the needle, and toensure proper presentation of the needle thread loops to the hook in alllateral positions or" the needlesgo 28. An attachment for a sewingmachine having a plurality of needles, means for reciprocating theneedles axially, means for throwing the needles to and fro laterally toa variable extent and a co-operating rotary hook, comprising;j,35

means having in combination a plurality of laterally movable membersattachable to the needle-reciprocating means, a needle-holding membervertically movable on each of said laterally movable members, and a pinon each of t the needle-holding members engaging a cam slot associatedwith said attachable member, in combination with means attachable to theneedle-throwing means for efiecting lateral throwing of the needles upto a total extent substantially equal to the diameter of the hook, saidcam slot being shaped to impart to the needles as they are moved tosuccessive lines of reciprocation from the beginning to the end of theeffective arc of the hook path such changes of height that the needlesreciprocate to lower dead centres which are progressively at a greaterdistance below said arc.

29. An attachment for a sewing machine having needle-reciprocating meansconstituted by a needle-bar movable vertically in fixed guides betweenfixed limits, means for throwing the needle to and fro laterally to avariable extent and a rotary hook actuable in timed relationship withthe needle bar and the needle throwing means,

comprising in combination lateral guide means attachable to theneedle-bar, a member variably laterally slidable on said guide means,vertical guide means on said member, a needle block slidable on thevertical guide means, the lateral guide means having a cam slot, and apin on the needle block engaging the cam slot, said cam slot beingshaped to cause such change of the height of reciprocation of the needlethat the time taken for the needle in any line of reciprocation to risefrom its lower dead centre to the effective arc of the hook path isequal to the time taken by the hook to reach the line of reciprocation.

30. An attachment for a sewing machine having means for reciprocatingthe needle axially, means for throwing the needle to and fro laterallyto a variable extent, and a rotary hook actuable in timed relationshipwith the needle reciprocating and throwing means, comprising incombination a multiplying lever attachable by pivot means to the machineand to the needlethrowing means, lateral guide means attachable to theneedle-reciprocating means, a member laterally slidable on said guidemeans, vertical guide means on said member, a needle block slidable onthe vertical guide means, the lateral guide means having a cam slot,said carn slot being shaped to ensure proper presentation of the needlethread loops to the hook in all lateral positions of the needle, a pinon the needle block engaging said cam slot, a vertical extension on thelaterally slidable member, a block member slidable on the said extensionand attachable by pivot means to the lever, the said several pivot meansbeing relatively located by the lever in such manner thatneedle-throwing movements are multiplied by the lever, said movementsbeing transmissible through the block member and the extension to thelaterally slidable member without hindering the vertical reciprocationsof the laterally slidable member.

31. An attachment for a sewing machine having needle-reciprocating meansincluding a needle bar vertically reciprocable between fixed limits,means for throwing the needle to and fro laterally to a variable extent,and a co-operating rotary hook, said attachment comprising incombination a plate attachable to the lower end of the needle bartransversely to the line of feed of the machine, horizontal slides onsaid plate, a member transversely movable in said slides, a rodextending vertically upwards from said member, a yoke slidable on saidrod and pivotally attachable to the needle-throwing means, verticalslides on said member, a needle block vertically movable in saidvertical slides, a pin projecting rearwardly from said needle block, avertical slot in said member, and a cam slotin said plate, said pinprojecting through said vertical slot and co-operating with said camslot, which is shaped to impart to the needle block as said member andsaid needle block are moved laterally by the needle-throwing meansthrough said rod and yoke such changes of height of reciprocation thatthe time taken by a needle secured in said blocks to rise from its lowerdead centre in any line of reciprocation to the effective arc of thehook path is equal to the time taken by the hook to reach the line ofreciprocation.

32. In a sewing machine, the combination of means for reciprocating theneedle axially, a rotary hook actuable in timed relationship with theneedle reciprocating means, means actuable in timed relationship withthe needle reciprocating means and the hook for variably throwing theneedle to and fro laterally up to an extent substantially equal to thediameter of the hook, and means ensuring proper presentation oi theneedle thread loops to the hook in all lateral positions of the needle.

33. In a sewing machine, the combination of needle reciprocating means,means effecting variable lateral throwing of the needle, a rotary hookactuable in timed relationship with said needle reciprocating andthrowing means, manually operable means controlling the lateral throwingof the needle up to an extent substantially equal to the diameter of thehook, means ensuring proper presentation of the needle thread loops tothe hook in all lateral positions of the needle, a take-up lever, afriction device adjacent said lever from which said thread passes tosaid lever, and means automatically varying the pressure of saidfriction device and consequently the tension of the needle thread withthe manually controlled variable extent of the throw of the needle.

NAHAM RAPAPORT.

EDWARD WEST ARMSTRONG.

OLIVER GEORGE HUTCH'INSON.

